Outlet Temperature Correlation and Prediction of Transfer Line Exchanger in an Industrial Steam Ethylene Cracking Process

doi:10.1016/S1004-9541(13)60472-8

Chin.J.Chem.Eng. ›› 2013, Vol. 21 ›› Issue (4): 388-394.DOI: 10.1016/S1004-9541(13)60472-8

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Outlet Temperature Correlation and Prediction of Transfer Line Exchanger in an Industrial Steam Ethylene Cracking Process

JIN Yangkun, LI Jinlong, DU Wenli, WANG Zhenlei, QIAN Feng

1 Key Laboratory of Advanced Control and Optimization for Chemical Processes of Ministry of Education, East China University of Science and Technology, Shanghai 200237, China;
2 Institute of Automation, East China University of Science and Technology, Shanghai 200237, China

Received:2012-05-15 Revised:2012-07-10 Online:2013-04-26 Published:2013-04-28
Supported by:
Supported by the Major State Basic Research Development Program of China (2012CB720500), the National Natural Science Foundation of China (U1162202, 21276078), the National Science Fund for Outstanding Young Scholars (61222303), the Shanghai Key Technologies R&D Program (12dz1125100) and the Shanghai Leading Academic Discipline Project (B504).

Outlet Temperature Correlation and Prediction of Transfer Line Exchanger in an Industrial Steam Ethylene Cracking Process

金阳坤, 李进龙, 杜文莉, 王振雷, 钱锋

1 Key Laboratory of Advanced Control and Optimization for Chemical Processes of Ministry of Education, East China University of Science and Technology, Shanghai 200237, China;
2 Institute of Automation, East China University of Science and Technology, Shanghai 200237, China

通讯作者: LI Jinlong, QIAN Feng
基金资助:
Supported by the Major State Basic Research Development Program of China (2012CB720500), the National Natural Science Foundation of China (U1162202, 21276078), the National Science Fund for Outstanding Young Scholars (61222303), the Shanghai Key Technologies R&D Program (12dz1125100) and the Shanghai Leading Academic Discipline Project (B504).

Abstract

Abstract: Predicting the best shutdown time of a steam ethylene cracking furnace in industrial practice remains a challenge due to the complex coking process. As well known, the shutdown time of a furnace is mainly determined by coking condition of the transfer line exchangers (TLE) when naphtha or other heavy hydrocarbon feedstocks are cracked. In practice, it is difficult to measure the coke thickness in TLE through experimental method in the complex industrial situation. However, the outlet temperature of TLE (TLEOT) can indirectly characterize the coking situation in TLE since the coke accumulation in TLE has great influence on TLEOT. Thus, the TLEOT could be a critical factor in deciding when to shut down the furnace to decoke. To predict the TLEOT, a parametric model was proposed in this work, based on theoretical analysis, mathematic reduction, and parameters estimation. The feasibility of the proposed model was further checked through industrial data and good agreements between model prediction and industrial data with maximum deviation 2% were observed.

Key words: transfer line exchanger, outlet temperature, parametric model, steam ethylene cracking

摘要： Predicting the best shutdown time of a steam ethylene cracking furnace in industrial practice remains a challenge due to the complex coking process. As well known, the shutdown time of a furnace is mainly determined by coking condition of the transfer line exchangers (TLE) when naphtha or other heavy hydrocarbon feedstocks are cracked. In practice, it is difficult to measure the coke thickness in TLE through experimental method in the complex industrial situation. However, the outlet temperature of TLE (TLEOT) can indirectly characterize the coking situation in TLE since the coke accumulation in TLE has great influence on TLEOT. Thus, the TLEOT could be a critical factor in deciding when to shut down the furnace to decoke. To predict the TLEOT, a parametric model was proposed in this work, based on theoretical analysis, mathematic reduction, and parameters estimation. The feasibility of the proposed model was further checked through industrial data and good agreements between model prediction and industrial data with maximum deviation 2% were observed.

关键词: transfer line exchanger, outlet temperature, parametric model, steam ethylene cracking

JIN Yangkun, LI Jinlong, DU Wenli, WANG Zhenlei, QIAN Feng . Outlet Temperature Correlation and Prediction of Transfer Line Exchanger in an Industrial Steam Ethylene Cracking Process[J]. Chin.J.Chem.Eng., 2013, 21(4): 388-394.

金阳坤, 李进龙, 杜文莉, 王振雷, 钱锋. Outlet Temperature Correlation and Prediction of Transfer Line Exchanger in an Industrial Steam Ethylene Cracking Process[J]. Chinese Journal of Chemical Engineering, 2013, 21(4): 388-394.

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Outlet Temperature Correlation and Prediction of Transfer Line Exchanger in an Industrial Steam Ethylene Cracking Process

Outlet Temperature Correlation and Prediction of Transfer Line Exchanger in an Industrial Steam Ethylene Cracking Process

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